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· Mosquito is a two-winged insect (also housefly and fruit fly). · The common genera of mosquito are: A. Culex (body held parallel to the surface while sitting) B. Aedes (= Stegomyia) ( body held parallel to surface while sitting, with black and white striped body) C. Anopheles (Body held at an angle to the surface, dark-spotted wing). · Female mosquitoes are bloodsuckers of vertebrates while the male sucks the plant juice. · Female mosquito is an ectoparasite (sanguivorous) and it is also an intermediate host for the pathogens like Plasmodium and Filaria. · Plasmodium can be called a hyperparasite because its host mosquito is a parasite. · Like other insects, the body of mosquitoes is divisible into the head, thorax, and abdomen. · Head bears a pair of antennae, compound eyes, and mouthparts. · In the adult mosquitoes, ocelli (simple eyes) are totally absent (in cockroaches and houseflies, ocelli are present). · ...

Periplaneta americana · Cockroaches belong to the class Insecta of the phylum Arthropoda . · Two species of cockroaches commonly found in India are  Periplaneta americana and Blatta orientalis. · The generic name Periplaneta was given by Burmeister (1838 AD) . · Periplanela americana is the largest and the most common species. · Cockroaches are cursorial (running) and nocturnal. · The adult P. americana measures 28‑44 mm in length and is dark brown in colour. MORPHOLOGY · Body is covered with the chitinous exoskeleton of sclerites. · Body is divided into head, thorax, and abdomen. · Head is derived by the fusion of six embryonic segments. · The sclerite of the head is fused to form a head capsule. · The part of the head between and behind the eyes is epicranium (vertex). (A) Male Cockroach    (B)Female Cockroach · The front of the head capsule is m...

· H. Stannius and Von Seibold coined the term Arthropoda  (Arthros = jointed; podos = legs). VVI Examples to Remember of Phylum Arthropoda for Entrance Exams of Nepal are: Peripatus (The connecting link between Annelida and Arthropoda) Aranea (Spider) Palamnaeus (Scorpion) Palaemon (Prawn) Cancer (Crab) Astacus Lepas Daphnia (Water flea) Cyclops Cray Fish Scolopendra (Centipede) Julus (Millipede) Lepisma (Silverfish) Cockroach, Grasshopper Dragonfly Housefly, Mosquito Springtails, Bristle tails Butterflies, Moths Limulus (King crab), Living fossil. Characteristics of Phylum Arthropoda · Triploblastic, segmented animals with joined appendages , organ-system level of body organization, · Tube within tube body plan. · Coelomate, true coelom restricted to gonads in adults. The body cavity is filled with hemolymph i.e. blood (Haemocoelomate). A. External features a) Bilaterally symmetrical b) Body is metamerically segmented; their number is generally f...